Wheelchair elevator for motor coach

ABSTRACT

A wheelchair elevator for a conventional coach body in which the floor of the coach is elevated substantially above ground level. A stepwell in the coach body has a step which is mounted at an elevation intermediate ground level and the floor level and includes a step frame upon which a step plate is mounted. The step plate is of substantial length so that it extends a distance behind the stepwell and beneath the floor of the coach body. The step frame includes rollers which mount the step plate for sliding movement laterally of the coach body. A hydraulic cylinder acts between the step frame and the step plate to move the step plate between a step forming position and an extended position in which it extends laterally beyond the confines of the coach body to provide a step surface of sufficient depth to accommodate a conventional wheelchair. A folding scissors-type linkage mounts the step frame on the coach body and maintains the step plate is a horizontal attitude while permitting its movement between a lowered position at ground level and a raised position at the level of the floor in the motor coach. A hydraulic cylinder assembly acts between each side of the step frame and the motor coach body to control vertical movement of the step frame.

United States Patent [191 Manning [4 1 Oct. 14, 1975 1 WHEELCHAIR ELEVATOR FOR MOTOR COACH [75] Inventor: Donald L. Manning, Orchard Lake,

Mich.

[73] Assignee: General Motors Corporation,

Detroit; Mich.

[22] Filed: July 26, 1974 [21] Appl. No.: 492,237

Primary ExaminerEvon C. Blunk Assistant ExaminerJames L. Rowland Attorney, Agent, or Firml-lerbert Furman ABSTRACT A wheelchair elevator for a conventional coach body in which the floor of the coach is elevated substantially above ground level. A stepwell in the coach body has a step which is mounted at an elevation intermediate ground level and the floor level and includes a step frame upon which a step plate is mounted. The step plate is of substantial length so that it extends a distance behind the stepwell and beneath the floor of the coach body. The step frame includes rollers which mount the step plate for sliding move ment laterally of the coach body. A hydraulic cylinder acts between the step frame and the step plate to move the step plate between a step forming position and an extended position in which it extends laterally beyond the confines of the coach body to provide a step surface of sufficient depth to accommodate a conventional wheelchair. A folding scissors-type linkage mounts the step frame on the coach body and maintains the step plate is a horizontal attitude while permitting its movement between a lowered position at ground level and a raised position at the level of the floor in the motor coach. A hydraulic cylinder assembly acts between each side of the step frame and the motor coach body to control vertical movement of the step frame.

2 Claims, 5 Drawing Figures US. Patent 001. 14, 1975 Sheet 1 of 3 3,912,048

US. Patent Oct. 14, 1975 Sheet 2 of3 3,912,048

U.S. Patant Oct. 14, 1975 Sheet 3 of3 3,912,048

WHEELCHAIR ELEVATOR FOR MOTOR COACH The invention disclosed herein was made in the course of or under a subcontract with the Department of Transportation The invention relates to a wheelchair elevator for the stepwell of a motor coach.

It is desirable in motor coaches used in mass public transit to provide a device for facilitating the entrance and exit of physically handicapped persons who travel in a wheelchair. It is desirable that such a wheelchair loading device be constructed for incorporation in a motor coach without necessitating substantial structural modification of the coach body. It is also necessary that such a wheelchair loading device not hamper the entry and exit of the able-bodied coach passengers. The present invention provides a wheelchair elevator device which is incorporated into the stepwell of the motor coach. 1

The wheelchair elevator device of the invention is adapted for use in a conventional coach body in which the floor of the coach is elevated substantially above ground level. The coach body has a stepwell in which a step is provided at an elevation intermediate ground level and the floor level. This step includes a step frame upon which a step plate is mounted. The step plate is of substantial length so that it extends a substantial distance beyond the stepwell and beneath the floor of the coach. The step frame includes rollers which mount the step plate for sliding movement laterally of the coach. A hydraulic cylinder acts between the step frame and the step plate to move the step plate from a normal step forming position in which its inboard end is stored beneath the coach floor to an extended position in which the step plate extends laterally beyond the confines of the coach body to provide a step of sufficient depth to accommodate a conventional wheel chair. The step frame is attached to the vehicle body by folding scissors-type linkages which maintain the step plate in a horizontal attitude while permitting its movement between a lowered position at ground level and a raised position at the level of the floor of the coach. A hydraulic cylinder assembly acts between each side of the step frame and the motor coach body to control vertical movement of the step frame.

One feature of the invention is that it provides a wheelchair elevator for a coach body in which a step of substantial depth has a normal retracted position in which its inboard end is stored beneath the floor of the coach and an extended position in which the outboard end of the step extends laterally outside the confines of the coach body to provide a step of sufficient depth to accommodate a wheelchair.

Another feature of the invention is that the step is mounted in the stepwell of the coach body by linkage means for moving the step between ground level and coach floor level.

These and other features, objects, and advantages of the invention will become apparent upon consideration of the specification and the appended drawings in which:

FIG. 1 is a perspective view of the motor coach wheelchair elevator in the normal step forming position;

FIG. 2 is a view similar to FIG. 1 but showing the wheelchair elevator in its lowered position at ground level;

FIG. 3 is a view similar to FIG. 1 but showing the wheelchair elevator in the raised position at the level of the floor of the motor coach;

FIG. 4 is a partial side elevation view of the wheelchair elevator in the normal step forming position; and

FIG. 5 is a front elevation view of the wheelchair elevator in the normal step forming position and having parts broken away in section.

Referring to FIG. 1, a motor coach body designated 10 is shown in phantom lines. The coach body 10 has a conventional door opening indicated generally at 12 which opens into a stepwell. The wheelchair elevator indicated generally at 14 is mounted in the stepwell of the motor coach and includes generally a step frame 16, a step plate 18 carried on the step frame 16, a pair of folding scissors-type linkages indicated generally at 20 and 21 which mount the step frame 18 on the coach body 10, and hydraulic cylinder assemblies 22 and 24 for controlling the elevation of the step frame 16.

Referring to FIGS. 4 and 5, it will be seen that the coach body includes a floor 26 which is at an elevation substantially above ground level. A stepwell 28 is provided in the coach body and is defined generally by sidewalls 32 and 34 and a rear wall 36. The floor of the stepwell is provided by the step plate 18 having a normal position as shown in FIGS. 1, 4 and 5 in which it provides a stop intermediate ground level and floor level upon which the motor coach passenger steps upon entry to and exit from the motor coach.

As seen in FIG. 5, the step frame 16 includes spaced C-shaped members 42 and 44 which are connected by a plate 46 extending therebetween and attached thereto by conventional nut and bolt assemblies 48 and 50. Both members 42 and 44 have a plurality of rollers 54 mounted along their length by shafts 56. Extension plates 62 and 64 are attached to the sides of the step plate 18 by nut and bolt assemblies 66 and 68. The extension plates 62 and 64 extend respectively within the C-shaped members 42 and 44 and ride on the plurality of rollers 54.

Referring to FIG. 4, the inboard end of step plate 18 extends a substantial distance beyond the back wall 36 of the stepwell 28 and beneath the floor 26. A clevis 72 is conventionally attached as by welding to this end of the step plate 18. A similar clevis 74 is conventionally attached as by welding to the plate 46 of the step frame 16. A conventional hydraulic cylinder 76 is attached to clevis 74 and has a piston rod 78 which is attached to clevis 72. Hydraulic cylinder 76 has a normal operating condition in which its piston rod 78 is extended therefrom to store the inboard end of step plate 18 beneath the floor 26. It will be apparent that operation of the hydraulic cylinder 76 to withdraw its piston rod 78 will effect sliding movement of the step plate 18 on the rollers 54 of the step frame 16 from the normal step forming position of FIG. 1 to the position of FIGS. 2 and 3 in which the step plate 38 is extended laterally of the coach body to provide a step surface of substantial depth for receiving a wheelchair as shown in phantom lines in FIGS. 2 and 3.

As best seen in FIGS. 4 and 5 the step frame 16 is mounted within the stepwell 28 by a pair of folding scissors-type linkages 20 and 21. The linkage 20 is connected to the step frame 16 by a pair of spaced upwardly opening U-shaped brackets 82 and 84 which are welded to the C-shaped member 42 and 44. The linkage 20 is connected to the coach body by a bracket 88 which has a flange 90 at its lower end attached to the floor 26 by nut and bolt assembly 92. The upper end of bracket 88 is reversely bent to provide downwardly extending legs 94 and 96. The linkage 20 includes links 102 and 104, 106 and 108. Link 102 has its upper end pivotally attached to leg 94 of bracket 88 by a pivot shaft and cotter pin assembly 112. The upper end of link 104 is similarly attached to the leg 96 by a pivot shaft and cotter pin assembly 114. The links 102 and 104 have respective longitudinally extending elongated slots 116 and 118 intermediate their ends. A bolt 122 extends through slots 116 and 118 and has a nut 124 on the end thereof so as to connect the links 102 and 104. A washer 126 is received on the bolt 122 between the links 102 and 104 so as to space the links apart and assure ease of sliding and rotating movement between the links 102 and 104. The end 128 of bolt 122 is of sufficient length to extend into a vertically extending guide slot 132 of a guide plate 134 which is attached to the side wall 34 of the stepwell and the bracket 88. Thus it will be apparent that the guide slot 132 defines the vertical path of movement of bolt 122 and in turn coordinates the movement of links 102 and 104 as it rides in their respective slots 116 and 118.

The lower end of link 106 is attached to bracket 82 by a pivot shaft and cotter pin assembly 138. The lower end of link 108 is similarly attached to bracket 84 by a pivot shaft and cotter pin assembly 140. Links 106 and 108 have respective longitudinally extending elongated slots 144 and 146 intermediate their ends. A bolt 148 extends through the elongated slots 144 and 146 and has a nut 150 thereon so that it connects the links 106 and 108. A washer 152 is received on the bolt 148 intermediate the links 106 and 108 to space the links apart and assure ease of sliding movement therebetween. The end 154 of the bolt 148 extends into the guide slot 132 of the guide plate 134 to define the path of vertical movement of the bolt 148 which in turn coordinates the movement between the links 106 and 108. The lower end of link 102 and the upper end of link 106 are pivotally connected together by a bolt, nut and spacing washer assembly 162. The lower end of link 104 and the upper end of link 108 are similarly pivotally connected together by a nut, bolt and spacing washer assembly 164. The linkage 21, as best seen in FIG. is a simplified form of a linkage and has its like elements designated by like numerals.

Vertical movement of the step frame 16 is powered by hydraulic cylinder assemblies 22 and 24. The hydraulic cylinder assembly 22 will be described, it being understood that the hydraulic cylinder 24 is similarly constructed and has like numbered elements. The hydraulic cylinder assembly 22 includes a pair of conventional hydraulic cylinders 172 and 174, FIG. 1, which are connected back to back. Hydraulic cylinder 172 has a piston rod 176 which is pivotally connected to the coach body 10. Hydraulic cylinder 174 has its piston rod 178 pivotally connected to the step frame 16 by a pivot 180. The hydraulic cylinders 172 and 174 have a normal operating position in which the piston rod 176 of cylinder 172 is fully withdrawn and the piston rod 178 of cylinder 174 is fully extended. With the hydraulic cylinders in this normal operating condition the step frame 16 assumes its normal step forming position of FIG. 1 in which the step plate 18 is at an elevation intermediate the ground level and the floor level of the coach. In this normal step-forming position the step plate 18 is at a convenient elevation for aiding the entrance and exit of able-bodied passengers.

In order to elevate a wheelchair into the motor coach, the coach driver initiates a control sequence which operates the various hydraulic cylinders to lower the step frame 16. Initially, the hydraulic cylinder 76 is operated to withdraw its piston rod 78 which in turn effects sliding movement of the step plate 18 on the rollers 54 of the step frame 16 from the step-forming position of FIG. 1 to the position of FIGS. 2 and 3 in which the step plate 18 is extended laterally outboard of the coach body. Next, the hydraulic cylinder 172 is actuated to cause extension of its piston rod 176 so that the hydraulic cylinders 172 and 174 and the step frame 16 are lowered to their position of FIG. 2 in which the step plate 18 is at ground level. At this level the wheelchair occupant can back onto the step plate 18.

After the wheelchair occupant is situated on the step plate, the coach driver operates the hydraulic cylinders 172 and 174 by causing the piston rods 174 and 176 to be withdrawn thereby lifting the step frame 16 vertically to its raised position of FIG. 3 in which the step plate 18 is at the elevation of the floor 26. The wheelchair occupant then backs off the step plate 18 onto the coach floor 26. The coach driver then actuates the hydraulic cylinder 174 to extend the piston rod 176 therefrom which in turn lowers the step frame 16 to its step forming elevation of FIG. 1. The hydraulic cylinder 76 is then actuated to extend its piston rod 78 which returns the inboard end of step plate 18 to its stored position beneath the floor 26.

It will be apparent that this operational sequence is reversed to unload the wheelchair from the motor coach. During the vertical movement of the step frame 16 by the hydraulic cylinder assemblies 22 and 24, the step frame 16 is maintained in horizontal attitude by virtue of the controlled folding action of the scissorstype linkages 20 and 21. In particular, the sliding cooperation of bolts 128 and 148 in the elongated slots 1 l6, 1 18, 144 and 146 and also in guide slot 132 cooperate to define the folding movement of the linkage 20 to maintain the step frame 16 in horizontal attitude as well as prevent swaying movement thereof.

Thus the invention provides a wheelchair elevator for a motor coach body.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a coach body having a floor elevated substantially above ground level, a door opening, and a stepwell opening toward the door opening, the combination comprising: a step frame located in the stepwell, linkage means mounting the step frame on the coach body for permitting vertical movement of the step frame and maintaining the step frame in a horizontal attitude, a step plate of substantially greater depth than the step frame and the stepwell, means movably mounting the step plate on the step frame, means for moving the step plate froma normal step forming position in which a portion of the step plate is stored beneath the coach floor to an extended position in which the step plate extends laterally outward of the coach body to increase the exposed depth of the step plate sufficiently to accommodate a wheelchair, and means for selectively effecting vertical movement of the step frame and associated step plate between the normal step forming position, a lowered position at ground level and an elevated position at the level of the coach floor.

2. In a coach body having a floor elevated substantially above ground level, a door opening, and a stepwell opening toward the door opening, the combination comprising: step means in the stepwell, the step means having a depth substantially greater than the depth of the stepwell, means mounting the step means in the stepwell for movement between a normal step-forming position in which the step means is partially stored beneath the floor and an extended position in which the step means extends laterally outboard of the coach body to increase the depth of the step depth sufficiently to accommodate a wheelchair, a folding scissors linkage means mounting the step means on the coach body in the stepwell to permit vertical movement of the step means and maintain the step means in a horizonttal attitude, a first hydraulic cylinder having one end connected to the coach body, a second hydraulic cylinder having one end connected to the step means, the other ends of the hydraulic cylinders being connected together, the first and second hydraulic cylinders having a normal operating condition in which one is extended and one is retracted to position the step means at a normal step-forming elevation intermediate ground level and floor level, the step means being positioned at ground level when both hydraulic cylinders are extended and being positioned at coach floor level when both hydraulic cylinders are in retracted position. 

1. In a coach body having a floor elevated substantially above ground level, a door opening, and a stepwell opening toward the door opening, the combination comprising: a step frame located in the stepwell, linkage means mounting the step frame on the coach body for permitting vertical movement of the step frame and maintaining the step frame in a horizontal attitude, a step plate of substantially greater depth than the step frame and the stepwell, means movably mounting the step plate on the step frame, means for moving the step plate from a normal step forming position in which a portion of the step plate is stored beneath the coach floor to an extended position in which the step plate extends laterally outward of the coach body to increase the exposed depth of the step plate sufficiently to accommodate a wheelchair, and means for selectively effecting vertical movement of the step frame and associated step plate between the normal step forming position, a lowered position at ground level and an elevated position at the level of the coach floor.
 2. In a coach body having a floor elevated substantially above ground level, a door opening, and a stepwell opening toward the door opening, the combination comprising: step means in the stepwell, the step means having a depth substantially greater than the depth of the stepwell, means mounting the step means in the stepwell for movement between a normal step-forming position in which the step means is partially stored beneath the floor and an extended position in which the step means extends laterally outboard of the coach body to increase the depth of the step depth sufficiently to accommodate a wheelchair, a folding scissors linkage means mounting the step means on the coach body in the stepwell to permit vertical movement of the step means and maintain the step means in a horizonttal attitude, a first hydraulic cylinder having one end connected to the coach body, a second hydraulic cylinder having one end connected to the step means, the other ends of the hydraulic cylinders being connected together, the first and second hydraulic cylinders having a normal operating condition in which one is extended and one is retracted to position the step means at a normal step-forming elevation intermediate ground level and floor level, the step means being positioned at ground level when both hydraulic cylinders are extended and being positioned at coach floor level when both hydraulic cylinders are in retracted position. 